Yet another item to my "wtf now" list. The past few weeks or so i have noticed sometimes my car seems to be running slightly to the right, about halfway between the midway and the next line up. IT does this usually in just average traffic or under acceleration. I decided to find out the numbers using the torque application to pull data from the ecu. the numbers i got were around 100 c-105c, usually sitting around 103c, under normal driving, and then just for the heck i took it up into the foothills and made the engine scream, it went to 109c before i turned the heat up in fear of killing the car. Is this normal operating conditions or are these signs of a more severe problem? Side note, the coolant flange is leaking in the back, but i made sure the coolant levels are proper, and i have a bad cat, could either of these be the culprit?

 

also note that oil temp is in normal specs during operation, between 200-210f, never more than that

 

Pulled the data for for the diagnostic run i did today, looks like the temp it seemed to want to hold the most was 102c, 215.6f, i dont know if this is spec or if it is supposed to be cooler, but that looks like the point it would try to cool down to, is that correct or is it supposed to be lower? oh and fans appear to be running normally.

 

The normal operating temp should be at or around 90 deg. celsius. It can be a bit higher while in slow traffic and such but it should be about 90. While 102 deg celsius won't do any damage it is too hot. Your leaking coolant flange is more than likely the problem. Any air that can get into the system will cause the thermostat to not open properly. Fix the coolant flange, bleed the system, clear any debris in front of the radiator/ a/c condensor, and your problem will most likely be fixed.

 

How old is your t-stat? How about the coolant temp sensor? What's the coolant look like color-wise? While a leaky coolant flange isn't ideal and should be fixed, it wouldn't be causing your car to overheat as long as the level of coolant didn't drop below the minimum.

Judging by the (apparent) accuracy of your temp readings I'd say its your t-stat rather than the sensor. When the sensor starts going bad it usually gives readings that are way out of the realm of possibility, like 150* C at a cold idle or 0* at what should be normal operating temp.